Akiyuki Dekai of Azabu University A research team of doctoral students, in collaboration with Keio University, Hokkaido University, and Kumamoto University, in a herd of Hadakadebanezumi, a worker rat who does not breed himself eats the feces of the Queen's pregnancy. He increased his motherhood and discovered that the Queen would become the babysitter after giving birth to her baby.
The naked mole rat digs a tunnel beneath a harsh semi-arid area and lives in groups of dozens of animals.Only a few males and one female, called the queen, breed, and the other females do not develop ovaries and are not sexually mature.This is a social structure that is rare in mammals and is called true sociality.The queen just gives birth and breastfeeds, and the working mice cooperate in raising children.However, although the breeding behavior is originally acquired by estrogen secreted from the ovaries during pregnancy, it is unclear how working mice, whose ovaries are underdeveloped and can hardly synthesize estrogen, increase their motherhood and become babysitters. rice field.
The research team focused on the daily coprophagy of the naked mole rat.When female working mice were fed the queen's feces during pregnancy for 9 days, the responsiveness to the bark of the pups increased in the test 4 days after the end of feeding.In addition, feeding the queen's feces after the end of the lactation period to which estrogen was added also increased the responsiveness to the bark of the pups.Oral ingestion of estrogen by working mice was able to reproduce the increased responsiveness of the queen's late childbirth to the bark of the pups, so the working mice received estrogen from the queen's feces that they could not synthesize by themselves and became maternal. It is thought that it is increasing.
Communication in which such hormones act on other individuals via feces to change their behavior has not been reported so far, and it is said that it is a discovery that provides a new concept of hormone action.
